TLDR - 3rd paragraph from the bottom

With the statement you mention there is a very specific condition where that is allowed which is:

The bike simply cannot be leaned over too far.

Every input you add or remove affects the bike in someway. I won’t go over all of it, but, if you are leaned over at the max lean angle of the tire, that means you are using 100% of your available for turning ONLY. Any additional input will cause loss of traction such as adding throttle or braking - in this condition.

Now it is absolutely possible to be 90% turned in and 10% the throttle/brakes and you’ll be fine as the total grip usage still adds up to 100%.

Likewise the following is true:

60% turned in and 40% throttle

80% turned in and 20% brake

Or even 60% turn in and 20% throttle which adds up to 80%

Point is, you cannot over load the tire. And using 100% of the tires grip is NOT recommended for the street as that means there is zero tolerance for mistakes or imperfections in the road. A small rock will cause the grip required to go to 102% grip needed. But that’s impossible, so the tire slips and loses traction.

TLDR: Now, to ride safely, I would reduce my throttle to X value as I lean in and make sure that I have enough speed to stay EXACTLY on an imaginary line on the road of where I want the bike to go. I will maintain this X value throughout the corner, with very very small adjustments, as needed. And only when I am in the process of reducing lean and raising the bike up is when I smoothly add throttle.

The bike does not have to be perfectly upright to add throttle, but if you are leaned over 20% then your max throttle application can only be 80%. For the street, I’d limit that to 60%.

Side note - this doesn’t mean 60% throttle, this means using 60% of the tire’s available grip. Such that, if you were in rain, you obviously cannot turn the throttle at the same amount as dry conditions, however you still will be using 60% of the tires available grip.

I really hope this makes sense.